Outlet-box.



OUTLET BOX.

APPLICATION FILED JAN. 12, 1907.

Patented Oct. 20, 1908.

nn-En STATE HARRY A. COFFIN, OF MALDEN, MASSACHUSETTS.

I OUTLET-BOX. f

To all whom 't may concern:-

Be it kno' nthat l, HARRY A. COFFI1-I citizen of the nited States, residing at'M-alden, in the county of Middlesex. and State of Massac 1setts, -have invented certain new and 'us fill Improvements in Outlet-Boxes, of wh'ch the followingis a specification;

M invention relates to the art of electric tec nrcally termed knob and: tube work.

he particular device which embodies my i provements consists of an outlet box, referably constructed of iron, through hich the main wirespass, and which is also adapted for combination work, i. 6., for the transmission of a gas pipe and electric cables through the same device. Such boxes are known in the art but require to be made in a variety of forms to suit various kinds of work, thus new work, old work, straight electric and combination require at least four sha es to adapt them flto the requirements of each class of work. #3 v The paramount object of my invention is to so design an outlet box for electric wiring that it may be readily adapted to the different conditions, thus romoting economy .in

themanufacture and saving time in constructive work.

Another object of my invention'is to provduce an outlet box for the purpose stated that will be simple'in construction and that can be produced at a minimunrcost by providing means for compensating for lack of uniformity in the castings.

I accompli. h the above and-other minor objects by the use of the device illustratedf drawing which forms in the accompanyin a art of this speci cation and in which:-

igure 1 is a front elevation of m improved outlet box for electric wiring; {Tig 2 1s a sectional View on the line 9.2 of Fig. 1; Fig. 3 is a transverse section" showing a modified form of diaphragm and bushing; Fig. 4 is a transverse section of the form seen in Figs. 1 and 2 showing the method of applying a cover to the box, and Fig. 5 is a front elevation of a modification of the ring casing. I Referrin to the drawing, 6. indicates a ring shape casing or rim provided with 'an inwardly projecting flange 7 which forms'a ledge upon which rests a diaphragm 8 furnished with a central aperture 8, surrounding which is a'fiange 9 having internal threads 10. The diaphragm or plate 8 is Specification of Letters Patent;

Application filed January 12, 1907; Aerial No. 352,009. 7

and has special reference to what Patented Oct. 20, 1906. i

I provided with a plurality of-ci'rcular openings 11, for the passage of flexible c'giruiduits. countersunk screw holes 12 are formed the said plate by means. of which the box on may be,secured in the desired location. A reduction bushing 13 aving. a projecting flange 14 is furnished with extern 1 threads to engage the internal threadsi O of the flange 9 the said/flange Q'eng'aging the flange, on the bushin'g'to hmitkits vertical moveg ment. The saidbushing has a central bore- 15 providedwith internal threads 16. TheSe' threads may be cut to a standard size to engage similar thr ds cut upon a gas pipe. when the combination system is employed.

In some cases it maybe desirable to close the box w' he cover 17 which has adepressed ce ter '18 and a central 0pening"19 through which the body of the reduction] bushing is passed and screwed down until the center 18 of the cover is held firml 'b'e- "tween the flange 14: of the bushin an the upper margin of the flange or-co ar 9, the

eriphery of the said cover resting upon. fhe. ree margin of the ring 6? c p f "'In Fi 3 is shown a modified form of reduction ushing and late. In thisi'case the f collar 9 is omitted an the central portion of. ,1 the plate,8 formed with an offset 20 the threads of the central aperture 8 being omitted. The modified form of bushing 21 is similar to the bushing shown in -Figs. 2 and-4 with the exce tion that the external threads are omitte the outside bein smooth and adapted to fit the opening 8 o i the plate 8. The flange 22 is received in the depression in the plate 8 formed by the ofl set 20, so that the free surface of said flange is flush with the corresp o ndin surface of the plate 8 The bushing" will ie thusheld, securely in place and the flan e will not in terfere with "the use oithe evice for old Work. u Q (:1

It is des' able for conveniencg in handling that the plate 8 and rim 6-should'h'ave a firm frictional contact so thatkthey will not become separated with ordina usage. As this will require some nicety o fitting, especially when the parts are made of cast iron, in'erder to enab e the parts in question to be assembled without preliminary finish; ,ing and thus promote economy in the mamb} iiacture'fiI rovide amodified .form ofrim "shown in, i5 5. The" part is in the Shit bevele to form a diagonal juncture 23, up

thus allow the ring to spread or contractto suit slight variations in the diameter of the plate 8.

The method of employing my improved outlet box for various kinds of work is as follows :.-For new work the box is to be 1 used in the complete form asshown in Figs.

apertures to receive attaching devices, a rim loosely surrounding and supporting said Y plate, a bushing having a threaded engagement with the central opening of said= plate, and means on said plate for limiting the vertical movement of said bushing in one direction.

2. An outlet box comprising a plate havin a threaded central opening and provi ed with apertures to receixye' Wires, a rim loosely surrounding said plate and ro; vided with a flange to receive the plate/{ a bushing having a threaded engagement with 'the central opening of said plate, and'pitovided With a flange, and a cover plate having a central opening to receive said' linsh- 111g, said cover plate bein arranged between said bushing flange an the first named plate, for the purpose set forth.

In. testimony WhereofI afiix my signature n presence of two Witnesses.

HARRY A. COFFIN. Witnesses:

HoRAcE W. SEX'roN, ALFRED Gr. Bnoons. 

